The Initialization Of Basal Sliding Coefficients For Antarctica, A Lyapunov Based Approach

International audience — Models describing natural phenomena can depend on parameters that cannot be directly measured, hence the necessity to develop inverse techniques to determine them. The goal of this paper is to utilize such a technique to enable better initialization of ice sheet models for A...

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Bibliographic Details
Published in:2018 Annual American Control Conference (ACC)
Main Authors: Mourad, Firas, Witrant, Emmanuel, Pattyn, Frank
Other Authors: GIPSA - Systèmes linéaires et robustesse (GIPSA-SLR), Département Automatique (GIPSA-DA), Grenoble Images Parole Signal Automatique (GIPSA-lab ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 )-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 )-Grenoble Images Parole Signal Automatique (GIPSA-lab ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 )-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ), Université libre de Bruxelles (ULB)
Format: Conference Object
Language:English
Published: HAL CCSD 2018
Subjects:
Online Access:https://hal.science/hal-01778305
https://hal.science/hal-01778305/document
https://hal.science/hal-01778305/file/2018ACC_0570_FI.pdf
https://doi.org/10.23919/ACC.2018.8431855
Description
Summary:International audience — Models describing natural phenomena can depend on parameters that cannot be directly measured, hence the necessity to develop inverse techniques to determine them. The goal of this paper is to utilize such a technique to enable better initialization of ice sheet models for Antarctica. This will enable models to produce better forecasts as part of climate studies. The parameter of interest is the basal sliding coefficient, which characterizes the contact of the ice sheet with the bed underneath. A Lyapunov based approach is proposed to control the convergence of the 1D inhomogeneous transport model toward a feasible equilibrium matching the measurements. This method results in a new update law for the coefficient inversion. The results, which show an improved convergence toward the observed ice thickness, are compared with a currently used inverse method.